Rot-protecting covering for wooden posts, sleepers, and the like



. E. WGRTMANN 2,148,334

COVERING FCR WOODEN POSTS. SLEEPERS, AND THE LIKE Feb. 21, 1939.

HOT-PROTECTING Filed Feb l8 1936 L R Q E/ V W/ V Z [ad 79 3f desiredquantity of Patented Feb. 21, 1939 BOT-PROTECTING COVERING FOR WOODENPOSTS, SLEEPERS, AND THE LIKE Ernst Wortmann, Schwelm, GermanyApplication FebruarylS, 1936, Serial No. 64,603

' In Germany November 6, 1933 1 Claim.

.This invention relates to a rot-protecting covering for wooden posts,sleepers and the like, to be placed on the wooden post or the like andcontaining an impregnating means which is gradually dissolved byatmospheric moisture and penetrates into the wood to be protected.

In the protecting covering according to the invention the rot-preventingimpregnating medium fills the meshes'or holes of a wide-meshed net or ofa grid serving as carrier for the impregnating salt. In such nets orgrids made of textile threads, for instance of jute,.threads or ofcotton threads, the impregnating substance further fills the gapsbetween the fibres of the threads. The mesh-width of the net or griddepends on the object to be fulfilled- Instead of a net or grid a porousor absorbent textile fabric may be employed. The impregnating salt isbrought into the meshes or -holes'of the net or of the grid by paintingthe net or grid with the impregnating substance or by saturating it witha liquid or pasty impregnating substance. The dissolved pastyimpregnating material remains sticking in the net or grid like carrierand, if the carrier consists of a textile fabric, for instance of coarsejute threads, it penetrates also in these threads. The quantity of theimpregnating paste to be absorbed can be easily regulated by the meshwidth and the thickness of the carrier. To improve theadhesion oftheimpregnating medium on the carrier a binding agent may be added.

The adhering of the impregnating medium on a net or grid shaped carriermade of textile threads can be considerably increased by roughening thesame. The textile fibres pulled out partly from the individual textilethreads by the roughening admix with the paste of impregnating salt whenthis paste is being applied and securely hold this paste on the carrierof the impregnating salt as if it was held by numerous small hooks.

This protecting cover can therefore hold any impregnating substancewhich, as it is completely detached or dissolved by the atmosphericmoisture, exerts its full effect. The protecting covering can be easilyproduced.

The impregnating liquid formed from the impregnating substance by thecontact with atmospheric moisture has the tendency to flow downwards,whereby for instance on wooden posts the wood portions situated athigher points are less impregnated than the wood portions situatedfarther down. In order to compensate for this the upper part of theprotecting cover has a trucker-layer of impregnating substance than thelower part so that from this upper part a 1 absorbed by the threads ofthe carrier.

' that end of the strip which on a vertical post forms the upper part ofthe wrapping contains more impregnating salts.

To prevent dissolved impregnating salts from penetratinginto the ground,at points of the post in and the like covered by the ground, the net orgrid carrying the impregnating substance is fixed on an outer layerimpermeable to water and consisting for instance of impregnated jute,asphalted cardboard and the like.

This form of construction has the especially advantageous effect thatnot the entire layer of impregnating substance is dissolved at once byan exceptionally large quantity of moisture, for instance by heavy rain.The meshes and 20 holes of the net or grid filled with impregnating saltform a very great number of impregnating sections, framed and separatedfrom each other by the threads of the net or grid, so that theimpregnating substance in these sections can be dissolved onlygradually.

An embodiment of the invention is illustrated merely by way of examplein the accompanying drawing in Fig. 1 in longitudinal section and inFig. 2 in elevation.

The carrier made of a textile fabric as net or grid is designated by aand carries commonly used impregnating salts. b is a support which isflexible and impermeable to water. The impregnating substance in liquidor pasty state fills the meshes or holes of the carrier a and is also Inrotpreventing covers in the shape of caps for post heads the support 6,forming the outer side of the cap, has a few holes, or it is lessstrongly imper- 4O meable to water so that the atmospheric moisture caneasily accede at the impregnating salt.

In Fig. 3 a net or grid-shaped carrier produced from textile threads isshown on enlarged scale, this carrier having been roughened prior to theapplication of the impregnating substance. By the roughening numeroustextile fibres c of short length have been pulled out. After theapplication of the impregnating substance the fibres are held in thissubstance and unite the same with the carrier.

The impregnating substance for filling the meshes and holes of thenet-like or grid-like car-= rier, may be of any suitable composition, amixture of dlnitrophenol 10%, sodium fluoride at i 10 inner layercomprising a wide meshed textile fabric adapted to contact the surfaceof the post, said fabric layer being impregnated with water soluble woodimpregnating salts, the meshes of said fabric forming relatively widerecesses, said recesses being filled with said salts, more of said saltsbeing lodged in said fabric adjacent one side edge of said band than islodged in said fabric adjacent the other side edge.

ERNST WOR'IMANN.

